The present invention relates to a chip conveyor for conveying chips produced by machine tools such as lathes from a collection position to a discharge position. Also, the present invention relates to an apparatus used in the chip conveyor for separating and collecting chips.
Japanese Unexamined Utility Model Publication No. 59-55645 describes a prior art chip conveyor. The chip conveyor includes a circulating carrier and a detachable bucket located at a chip discharge position. Chips with cutting oil are conveyed to the discharge position by the carrier and are received in the bucket when the carrier curves to the discharge position. Many small holes for screening oil are formed in the bottom of the bucket.
A nozzle blows air against a lower surface of the carrier so that chips adhering to the lower surface of the carrier fall into the bucket. Oil on the chips passes through the small holes of the bucket and is collected outside the bucket through an oil tube.
However, in the above chip conveyor, the force of air blown from the nozzle is not strong enough to separate and collect all the chips adhering to the lower surface of the carrier. It is possible to separate the chips from the carrier by increasing the air pressure in the nozzle. However, this requires a special structure for preventing chips from being scattered and a supply source of high-pressure fluid.
On the other hand, the present applicants have suggested another chip conveyor, which is described in Japanese Unexamined Patent publication No. 63-123656. In the chip conveyor, an endless mesh belt is located inward of a horizontal frame and an inclined frame. Also, a chip collection tank is located at a chip collecting position. Circulation of the belt conveys chips into a chip collection tank, which removes chips from the belt. Also, a spray is located between the upper run and the lower run of the mesh belt in the horizontal frame. The spray discharges cleaning liquid against the lower run of the mesh belt, which cleans the lower run.
However, spraying cleaning liquid against the mesh belt cannot remove all the chips. Also, the chip conveyor requires a special structure for preventing splatter of the cleaning liquid and preventing the chips from scattering, and a source of high pressure fluid is also required.
If some of chips are still attached to the carrier such as a belt after the carrier passes a chip discharge position, the remaining chips may enter between contacting parts that form the carrier and the driving mechanism of the carrier, which wears the parts and shortens the life of the driving mechanism. If the remaining chips fall from the bucket at the collecting position and form a pile, which is troublesome to remove manually.
The present invention was developed to solve the above problems. That is, an objective of the present invention is to provide a chip conveyor that extends the life of the carrier and the driving mechanism by removing chips from the carrier that pass through the chip discharge position and reach the chip collection position.
Another objective of the present invention is to provide a simplified apparatus for separating and collecting chips that facilitates attachment and detachment to the discharge portion of the chip conveyor.
To achieve the above objectives, the preferred embodiments of the present invention provide a chip conveyor that collects chips discharged from machine tools at a collection position and has an endless carrier arranged to circulate in a predetermined direction. The carrier of the chip conveyor travels on an upper path from the collection position to the discharge position and travels on a lower path when returning from the discharge position to the collection position. A reservoir tank is located in the lower path of the carrier. Chips attached to the carrier are separated from the carrier in the liquid of the reservoir tank when the carrier is in the tank.
Preferably, a part of the carrier corresponding to the lower path takes a roundabout route downward to separate from a part corresponding to the upper path and enters the liquid of the reservoir tank. A discharging means for discharging chips from the reservoir is preferably provided in the reservoir. A supplying means for supplying liquid is preferably provided in the reservoir tank. In the preferred embodiments, a collecting tank is located at the collecting position, and the carrier passes through the collecting tank. The discharging means includes a means for sending excess liquid to the collecting tank.
In another embodiment of the present invention, an apparatus for separating and collecting chips is used in the chip conveyor. The apparatus includes a reservoir tank, which is located in the lower route and accommodates liquid through which the carrier passes and a roundabout mechanism, which is located in the reservoir tank and gives the carrier a roundabout route.